Bulk bag pack and method of making same



7 April 2, 1957 w. G. SHEARD BULK BAG PACK AND METHOD OF MAKING SAME Filed May 17, 1954 k INVENTOR. WILLIAM G. SHEARD TORNEYS 2,787,372 BULK BAG PACK AND Nmrnon OF MAKING SAME William G. Sheard, North Olmsted, Ohio Application May 11, 1954, Serial No. 430,205 10 Claims. Ci. zoo-=65 This invention relates, as indicated, to a bulk bag pack and is particularly adapted for handling loose aggregate in bags in a bulk bag wrap which contains from twenty to forty bags, convenient for handling with modern material handling e uipment. Basically, the bag pack consists of an outer wrapper of relatively high tensile strength, perhaps a fibrous paper, a central, heavy wall tube made of spirally wound aper, and bags of loose aggregate material filled therein, which are staggered in relationship to one another. The outer wrapping of paper, possibly sisal reinforced, would be tensioned around the bags while being subjected to vibration, and then sealed o'r fastened by some ineans, such as a quick sealing adhesive. The bags, themselves, could be secured together by a special adhesive, which is high in shear strength and low in tensile strength, to resist bags sliding out the ends of the bulk bag pack or in relationship to one another.

This invention particularly relates to a bulk bag pack which may range in Weight from two to four thousand pounds, and would contain perhaps twenty bags 1:6" 24" containing from eighty to one hundred pounds of an aggregate material. At the center of the package there would be a spirally wound tube, perhaps 3 /2 inches in diameter, which would be convenient for handling with material handling equipment, having a special prong or spear to lift up the bulk bag pack.

An object of this invention is to develop a novel type of bulk bag pack, and apparatus therefor, having an outer covering of material such as paper, a central tube of spirally wound paper, or equivalent means, and a plurality of loose aggregate bags in staggered relationship to one another in the pack.

A further object of this invention is to produce a new method of providing a bulk bag pack for loose aggregate by containing the material in a form which makes for the maximum use of the materials involved, and by using the method of filling the pack which will contain the loose bag aggregate in an outer wrapping or skin which is under tension.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims; the following description setting forth in detailv one approved method of carrying out the invention, such disclosed method, however, constituting but 'one of the various ways in which the principles of the invention may be used.

Fig. -l is a cutaway perspective view of the bulk bag ack, p P Fig. 2 is a view of the bag .pack immediately before assembly, Y

Fig. 3 is a view of the closing apparatus, and

Fig. 4 is an end view of the gripper for the heavy covering material. v v p r I This invention relates to a bulk bag pack, which might be from two to four thousand pounds in size, able to nited States Patent ice hold loose bags of aggregate, perhaps as many as twenty, more or less, weighing from eighty to one hundred pounds. Said bags would be positioned longitudinally and crosswise, much as bricks are placed, and would have on the outside skin or cover thereof a layer of paper. Centrally of the cylindricall'y shaped bulk bag pack there would be a spirally wound tube. In this invention it shows the form or container which is semicylindrical. 11 shows a shelf or ridge portion at the top of the form. Said form may be mounted flush with the floor or may be raised in some manner. The model that is flush with the floor might be more convenient for loading. Bags which would be normally 16" x 24" might contain from eighty to one hundred pounds.

It has been found difficult in the past to palletize these bags. Up until the present time there has been no convenient method of handling bags at very low cost. This would be a bulk bag pack able to hold quite a number of bags, to be conveniently handled by modern material handling equipment. In this modification there is a clamping portion 12, which is hinged as at 13, having a handle 14. Pivotally mounted at 15 is a second portion 16, having a hook 17. A tapered gripping member 23 is used to support the opposite end of the paper that surrounds the bulk bag pack. The inside surface of the arcuate clamping portion 12 is coated with an abrasive material 21 so that a sure grip can be provided on the paper. The tapered gripper 23 comprises an elongated member 26 as long as the bulk bag pack, perhaps 48 inches. Said member would have a rod 24 which would be slightly serrated or roughened, as by knurling, to provide grooves and ridges which cut into the paper. The paper would be inserted in the mouth 18 of said elongated gripper 23 and would catch against the roughened surface 19. The paper would be pushed past the rod 24 and tension would be applied by means of the hook 17 aforementioned, and a loop of wire 25, which is secured to the gripper at 26. As tension is ap plied to the gripper the paper would pull the roller 24 into the V shown generally at 22 of the gripper, and since the roller is serrated and the other portion of the gripper on the sides has an abrasive surface, a firm grip would be held therebetween, so that the paper surrounding the bulk bag pack could be brought under considerable tension, perhaps of the order of one or two thousands pound tension.

A bulk bag pack would be formed by inserting bags in the form 10 aforementioned. Perhaps the bag at the bottom of the semi-cylindrical form 10 would be placed one following the other, transverse to the axis and side by side. The next four bags might be placed longitudinally and then three more transverse. The tube 27 would be inserted at this point and then three more bags transverse, fou'r longitudinal and three transverse would be added in layers. The above mentioned tube could be 3% inches, more or less, in diameter, and could be formed from paper. Under some conditions it might have to be made of special paper of high wet strength or of wet and dry strength, which approximately equals for some uses. Under some conditions it could be coated with a waterproof coating, as for example asphalt.

if possible, more than 50% of the bags would be "placed below the tube, so that upon lifting there would handle 14 would be held in tension so that the gripper could be attached to the other end of the paper surrounding the bags. When the vibration period is over, the adhesive 29 on the cover 28 would set to put the cover in tension around the bags. By this packing method tension of the order of one to two thousand pounds, meaning about twenty pounds per linear inch of length, must be placed on the cover A paper capable of withstanding this tension perhaps would be fifty thousandths paper, i. e., having a thickness of .050 inch, and to prevent incipient tear might be sisal reinforced circumferentially around the bulk bag pack.

Between the bags at 30 would be a special adhesive, which would have a high shear strength and a low tensile strength. This would lock the bags relative to one another in shear so that the bags in the bulk bag pack would resist bag sliding. An example of an adhesive such as this is lod-lok adhesive. Other materials which might work would be a double sided pressure sensitive tape or a rubber frictional tape. Further in connection with the packaging there would be a vibrating apparatus which is shown generally at 31 to compact the loose aggregate.

The high shear low tensile strength adhesive would be in some contrast to the adhesive used to seal the ends of the bag together. In this case the adhesive would be of high shear strength and quick setting, so that the tension would not have to be maintained for any period of time.

In connection with this bulk bag pack it should be noted that the tension at all times must be approximately equal in each portion of the circumferential supporting, thinand flexible materials. This means that a bulk bag pack could not be supported in the vertical plane because tension would then become quite large on the lower end because of the head or Weight of the materials on this segment.

One of the reasons why this particular bulk bag pack is effective is that the cylindrical form goes around the greatest quantity of material of any particular shape. Besides that there are no particular stress concentrations and the cylindrical form will spread the load on the skin, or outside area, over as wide an area as possible. When being held by the central pilot it will be seen that the top segment of the bag will be in compression and the lower portion in tension. When placed on the ground, as for example on a flat surface, the bulk bag pack does not loosen but rather tightens, as the weight of the bag tends to force the bag out laterally, forming a flat oval, and prevents any of the bags from slipping out. The addition of the adhesive aids in preventing bags from slipping out. The spirally wound paper tube in the center must, of course, be sufficiently rigid and strong to resist the crushing loads involved. In the position while suspended in material handling equipment, it will be seen that the top segment is under considerable compression, but as distinguished from some geometrical shape having a flat side, there is no stress concentration which would tear the bag. However, the load must be distributed along the entire length of the bulk bag pack, or the thin and flexible covering or skin would rip and tear. The action of this bulk bag pack can best be understood when it is realized that the material is a semi-fluid mass and will flow to a certain extent. particularly when packed using a vibratory force, mentioned earlier, or if it should be set on end it will be seen that the force on the last segment of the bag would be quite high, because the head of the material positioned immediately above it might be suflicient to tear the covering.

This invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are, therefore, to be considered in all respectsas illustrative and not restrictive, the scope of the invention being indicated by the appended claims, .rather than by the foregoing description, and all changes that come within the meaning and range of equivalency of the claims are, therefore, intended to be embraced therein.

I claim:

1. A bulk bag pack comprising an outer generally cylindrical member of thin and flexible materials, a generally centrally positioned hollow tube, and a multiplicity of bags placed in the generally cylindrical outer member and around the tube in a staggered relationship to one another, the cylindrical outer member being in tension around the bags.

2. A bulk bag pack having a hollow central tube, a multiplicity of bags in staggered relationship to one another surrounding the tube, and a thin and flexible outer container surrounding the bags in tension, the tension in said outer member being approximately equal throughout its length.

3. The bulk bag pack of claim 1, in which the outer cylindrical member is of paper, and the tube of spirally wound paper.

4. The bulk bag pack of claim 1, in which the individual bags are secured to one another by an adhesive which is low in tensile strength and high in shear strength, in order to prevent the bags from slipping out of the bulk bag pack.

5. A bulk bag pack adapted for material handling equipment and to be held in a horizontal position, comprising a generally cylindrical tube which is rigid and of relatively high compressive strength, a multiplicity of bags in staggered relationship around said central tube ,in the shape of a cylinder, said bags being secured to one another by an adhesive which is high in shear strength and low in tension, an outer covering surrounding said tube and bags which is in tension, the tension in each segment being approximately the same throughout the length of the cylinder.

6. A method of packing bags of aggregate in a bulk bag pack, which comprises forming an outer covering in a semi-cylindrical form, and piling bags in staggered relationship with respect to one another, forming a longitudinally extended aperture above the center of the bulk pack, which aperture is adapted to receive a spear-like lifting device, and continuing to pack the bags to approximate the complete cylinder, tensioning the cover around the bags while subjecting the bagged aggregate to a vibratory force to compact the same, and secure the ends of the cover while being tensioned.

7. The method of packing a bulk bag pack which consists of forming a covering in a semi-cylindrical shape, packing bags therein to fill the semi-cylindrical shape, continuing the shape until it is a full cylinder, forming a longitudinally extending aperture above the center of the bulk pack, which aperture is adapted to receive a spear-like lifting device, applying a vibratory force in a vertical direction to said bulk bag pack while the ends of the covering are under tension and fastening the same.

8. The method of'claim 7 in which the longitudinally extending aperture is positioned above the geometric center of the bulk bag pack so that the center of gravity is below the aperture, whereby a bulk bag pack is produced which may be carried with mechanical handling equipment by means of a spear-like device.

9. An apparatus for forming a bulk bag pack with a covering for the contents of the bulk bag pack of a thin and flexible member, which apparatus consists of a semicylindrical member, an arcuate segment supported at the top of the.semi-cylindrical member and along one side thereof, said segment having means for applying a pressure against the contents to be packed, said segment having a roughened surface on the concave face thereof to grip the covering and contents, means for fastening to the thin and flexible member so that tension in any segment is substantially the same along its length, and means for vibrating the apparatus while exerting said tension on the thin and flexible covering member surrounding the contents.

10. An apparatus for forming a bulk bag pack comprising an elongated semi-cylindrical member, means in connection with said semi-cylindrical member for vibrating the same in a vertical direction, means on the longitudinal edge of said semi-cylindrical member for gripping the covering of the contents, means in connection with said concave portion for gripping the end of the covering for the contents of the bulk bag pack to apply a tension to the covering while the vibratory force densifies the contents, 3. sheet gripper particularly adapted for tightening the covering around a bulk bag pack which comprises an elongated member having an open side which is generally tapered, a serrated rod within said elongated member and a frictionally gripping surface on one side of said elongated member holding the covering between the rod and the elongated member.

References Cited in the file of this patent UNITED STATES PATENTS 995,939 Anderson June 20, 1911 1,194,492 Fischer Aug. 15, 1916 1,491,269 Joplin Apr. 22, 1924 2,091,726 Woodward Aug. 24, 1937 2,276,541 Howard Mar. 17, 1942 2,350,418 Ross June 6, 1944 2,566,385 Van Patten Sept. 4, 1951 2,596,071 Friesner May 6, 1952 2,609,923 Simonton Sept. 9, 1952 

